Dishwashing apparatus

ABSTRACT

A dishwasher arrangement in which food particles separated from the articles being washed are separated from the water being circulated to effect the washing by momentarily stopping the circulation of the water in the washing chamber to permit the level of water in the sump to rise sufficiently to sweep the food particles out of an opening provided in a washing chamber wall.

United States Patent Mamrose [4 1 June 13, 1972 [54] DISHWASHINGAPPARATUS 2,314,048 3/1943 Ladewig ..l34/ 104 3,465,761 9/1969 Meeker etaL. ....l34/58 D [721 weley Magnus Lane 3,498,304 3/1970 Rumbaugh..134/53 1) lrwm, Pa. 15642 2 Filed; Sept 29 970 Primary Examiner-RobertL. Bluetge Attorney-F. H. Henson and E. C. Arenz [21] Appl. No.: 76,560

[57] ABSTRACT [5 2] 0.8. CI. ..l34/58 D, 134/104 A dishwasherarrangement in which food particles separated [51] Int. Cl. .B08b 3/02,B08! 15/00 from the articles being washed are separated from the water[58] Field of Search ..l34/58 D, 95, 96, 104 being circulated to effectthe Washing y momentarily stopping the circulation of the water in thewashing chamber 56] References Cited to pemlit the level of water in the.sump to rise sufficiently to sweep the food particles out of an openingprovided in a washing chamber wall.

3 Claims, 5 Drawing Figures PATENTEDJun 1 3 I972 3.669.132

sum 1 or 2 INVENTOR Wesley Mam rose ATTORNEYL PATENTEDJUH 1 3 I972 SHEET2 0F 2 l l TlMER FIG. 4

DRY

I WASH IRINSE l RINSE l PRE RINSE IIII II II IIIDII II II. E IIDII ll U2 00 L ll HUI D U 8 +%Li M W M T 8 y L V O 0 A M R R V N N E E L M 11 TW H R A M T F D M H DISHWASHING APPARATUS BACKGROUND OF THE INVENTION 1.Field of the Invention This invention pertains to the art of separatingfood particles in a dishwasher from the water being circulated to efiectwashing and rinsing.

2. Description of the Prior Art In conventional dishwashers of which Iam aware, one arrangement commonly used to separate water forrecirculation in the dishwasher from food debris washed from thearticles in the washing chamber is to pass the recirculation waterthrough a screen which strains the food particles therefrom and directsthe food particles into a space from which they are subsequentlydirected to drain when the washing or rinsing water is also flushed todrain. U.S. Pat. Nos. 3,034,518 and 3,210,009 are exemplary of sucharrangements generally. The undercounter, and floor supported portabledishwashers in which such arrangements are typically provided areusually of sufficient height that no particular problem is encounteredin providing a sloping screen arrangement which tends to channel anddirect the food particles into a particular part of the sump. However,in a dishwasher in which the height of the machine is limited, such as aso-called countertop dishwasher, the provision of a screen withsufficient slope to direct the food particles during recirculation ofthe water to a particular space presents problems.

Accordingly, I have devised a way, especially useful in connection withportable countertop dishwashers, although not so limited in use, inwhich food particles and debris may be separated from the recirculationwater without the provision of a screen of substantial slope.

SUMMARY OF THE INVENTION In accordance with my invention, and asembodied in the countertop dishwasher, I provide a washing chamber withan underlying sump and a screening wall between the chamber and thesump, an opening in one of the walls at about the level of waternormally obtaining during the circulation of water, and means formomentarily interrupting the circulation of the water during at least awashing or a rinsing operation for a sufficient period that the waterdropping from the washing chamber space and off the articles beingwashed raises the level of the water in the chamber sufficiently tosweep the food particles and debris off the screening wall and out ofthe washing chamber through the opening provided in one of the sidewalls. In other words, I utilize the quantity of water being flung aboutthe washing chamber and on the articles being washed to raise the levelof water sufficient to sweep the food particles in a fashion analogousto a tidal wave.

DRAWING DESCRIPTION FIG. 1 is a front elevation, partly broken, partlyin section, and partly diagrammatic, illustrating a countertopdishwasher in which the invention may be embodied for example.

FIG. 2 is an interior isometric view directed toward the right, rear,lower corner of the washing chamber with a part of the wall of the motorcompartment broken away;

FIG. 3 is a generally diagrammatic view in the nature of a horizontalsection through the base of the unit illustrating the generalrelationship of the pump, supply and drain conduits;

FIG. 4 is a simplified schematic of a control arrangement which may beused in accordance with the invention; and

FIG. 5 is a chart illustrating a typical operational program for adishwasher in which the invention may be embodied.

DESCRIPTION OF THE PREFERRED EMBODIMENT The main parts of the countertopdishwasher shown in FIG. 1 include a base section 10, a washing chambersection 12, and a motor and control compartment 14. The wash chamber 12is of generally rectangular box form and includes a rear wall 16, leftand right side walls 18 and 20, top wall 22, and a front hinged door 24for access to the: washing chamber space. The bottom of the washingchamber is defined by a foraminous member such as a plastic screen 26overlying a sump space 28 defined on its bottom by the sloping bottomwall 30 of the base section 10.

Among the elements to be found in the machine compartment 14 is a timer32 for controlling the duration of certain operations in the totaloperating cycle, a main motor 34 which drives the impeller 36 of a pump38 connected to the motor by shaft 40. A control knob 44 is manuallyturned to energize the timer, with the timer then turning the knob withit as the operating cycle proceeds.

The sump space 28 underlying the washing chamber is in communicationwith the inlet 46 of the pump 38. The outlet of the pump 38 is connectedto a conduit 48 molded into the plastic base section for deliveringwater from the pump to one or more rotating arms 50 overlying the screen26. The arm 50 is driven by the water being forced through the arm sothat the arm flings the water about the washing chamber space and on tothe articles (not shown) in the washing chamber for cleaning.

Water is initially supplied tothe chamber from a connection to a houseline, such as through the: kitchen sink top, and through a supply linehaving a valve 521 controlled by the timer 32. The volume of wateradmitted during the various portions of the cycle may be controlled inaccordance with time as is conventional, or by any other conventionalmeans to provide the proper amount of water in the washing chamber forthe particular operation to be carried out.

The water admitted to the washing chamber passes down through thescreening wall 26 and flows along the bottom wall 30 to the inlet of thepump 38 and is then forced back through the conduit 48 to the rotatingarm 50 and flung about the washing chamber space. The screening wall 26is designed with holes of a diameter that is a substantial portion ofthe food particles washed off the articles being cleaned are retained onthe surface of the screening wall 26, with the quantity of water in thewashing chamber and in the circulating system being such that the levelof water is about that level corresponding to the top surface of thescreening wall 26.

Referring now to FIG. 2, the right side wall 20 of the washing chamberis provided with an opening 54 therein which is slightly above the levelof the screening wall 26. In the machine compartment 14, a passage isformed by a horizontal wall 56 and an adjacent vertical wall5i8 whichlead to a food particle and debris collecting chamber 60. This debriscollecting chamber is in open communication with the drain pipe 62 (FIG.3) which extends for the length of the base of the dishwasher and alongits rear, and is open-ended at both ends to permit a drain connection tothe kitchen sink to be made from either end with the opposite end beingcapped. The location of the debris chamber 60 relative to the underlyingdrain pipe 62 is indicated by the broken line box of FIG. 3.

FIG. 3 also shows the relative location of the pump 38 and itsconnection to the conduit 48 leading to the spray arm 50, and theprovision of a pump-out drain line 64 which communicates at its one endwith the conduit 48 and is connected through a drain valve 66 controlledby the timer 32 to the drain pipe 62.

The dishwasher is also provided with the usual heater 68 for promotingthe drying of dishes after washing and rinsing operations are completed.

A simplified schematic of a control system is shown in FIG. 4, with achart indicating the various periods of energization of the electricalparts of the system shown in FIG. 5. It will be appreciated that varioussequences of operation may be provided in accordance with the invention,the sequences shown in FIG. 5 simply being an example in which apre-rinse operation is available.

To operate the dishwasher the timer knob 44 is first manually rotated toclose the switch 70 to energize the timer motor 32. Thereafter operationof the timer effects closure and opening of switches 72,74, 76 and 78 inaccordance with the selected operational program, as shown in FIG. 5 forexample. Those versed in the art will find the chart of FIG. 5selfexplanatory, it is believed.

In accordance with the invention the supply of water admitted to thewashing chamber is such that during operation of the pump 38 the levelof water is about that level of the upper surface of the screening wall26. Then, shortly after the water has been admitted and is being flungabout the washing chamber by the rotating arm 50, the main motor 34 ismomentarily interrupted during its energization as at 80, in theprerinse operation and at 82 in the wash operation. During suchinterruptions the airborne or suspended water in the washing chamberspace drops back down onto the screening wall 26 and raises the levelsufficiently to swamp" the sump with a water motion similar to a tidalaction. The food particles on the screening wall 26 move with the waterflowing out the overflow opening 54 and into the collection chamber 60in communication with the drain pipe. Thus the food particles areseparated early during a rinsing or washing operation from the remainderof the water which is to be recirculated.

It is to be appreciated that the operation according to the invention isnot limited to countertop dishwashers but finds its best applicationtherein for the reasons outlined hereinbefore.

What I claim is:

1. In a dishwasher:

a washing chamber including side walls and a top wall for containingarticles to be washed;

a sump underlying said chamber;

a screening wall between said chamber and sump;

means for circulating water from said sump to the space in said chamberand upon said articles for accomplishing washing and rinsing of saidarticles;

means for draining said sump;

an opening in one of said side walls at about the level of waternormally obtained during said circulation of water; and

timing means for controlling said circulating and said drainingoperations, including means for momentarily interrupting circulation ofsaid water during at least one of said washing and said rinsingoperations for a sufficient period that water dropping from said spaceand off said articles being washed so raises the level of the water insaid chamber as to sweep food particles on said screening wall out ofsaid washing chamber through said opening, and for then resuming saidoperation.

2. In a dishwasher according to claim 1 wherein:

said draining means is maintained in a closed position during saidinterruption of circulation of said water.

3. In a dishwasher according to claim 1 wherein:

said dishwasher comprises a countertop dishwasher of relatively limitedheight; and

said screening wall is substantially planar.

1. In a dishwasher: a washing chamber including side walls and a topwall for containing articles to be washed; a sump underlying saidchamber; a screening wall between said chamber and sump; means forcirculating water from said sump to the space in said chamber and uponsaid articles for accomplishing washing and rinsing of said articles;means for draining said sump; an opening in one of said side walls atabout the level of water normally obtained during said circulation ofwater; and timing means for controlling said circulating and saiddraining operations, including means for momentarily interruptingcirculation of said water during at least one of said washing and saidrinsing operations for a sufficient period that water dropping from saidspace and off said articles being washed so raises the level of thewater in said chamber as to sweep food particles on said screening wallout of said washing chamber through said opening, and for then resumingsaid operation.
 2. In a dishwasher according to claim 1 wherein: saiddraining means is maintained in a closed position during saidinterruption of circulation of said water.
 3. In a dishwasher accordingto claim 1 wherein: said dishwasher comprises a countertop dishwasher ofrelatively limited height; and said screening wall is substantiallyplanar.